Diablo is 13 years old, Diablo 2 is 10. 3 years inbetween, made before save continuity was really even considered as a game mechanic. Torchlight is closer, but like diablo its sequel has completely different characters. Thats very different than a modern game with the same main character, with 2 games being made in conjunction. If something didnt work with the save transfer, they had the oppurtunity to easily change it in game 1 and 2. Not many developers get that chance. But they took the easy way out, and avoided it all together. The deathspank crew had a perfect oppurtunity to implement save continuity bonus's, and they arn't even doing a token, thanks for playing both games little secret item from the sound of it.
As for save continuity being too complex for deathspank, the developers can make it as complex as they want and are willing to put time into. For this game, they decided on 0. At the least, they could have had some bonus hat or something, that you get for 100% on the first game, which doesn't affect gameplay at all, and let you take it into game 2. Just as a token for the 100% from game 1.
I'm not saying the games are bad or they are not delivering what they promised. But I, and i'm sure many other gamers are dissapointed that save continuity is not in the game. Especially given the huge opportunity these games had to do it right, given the simultaneous production and back to back release. Game 1: you save the world, congrats. Game 2: 2 months have past, all your weapons are gone, your back to level 1 do it all over again. Atleast the writers will probably think of some funny tongue in cheek joke reason as to why your starting all over.